Analysis of random error influencing factors in the three-point method for center of mass measurement

Abstract To address the challenges of measuring the centre of mass of small drones and irregular devices—including measurement complexity, insufficient accuracy, and cumbersome procedures—this study presents a simple yet highly precise centre of mass measurement device. The device relies on a parallel mechanism and uses a three-point measurement principle to accurately, flexibly and quickly determine the position of the centre of mass of an object in space. The centroid measurement error model was constructed based on the Monte Carlo Method by thoroughly analysing the influence of random errors in each structural parameter of the measurement system on the measurement results. Through simulation experiments, the distribution of random errors during measurement was obtained in two states (a certain range of pose angles and different measurement positions). Subsequently, a weight analysis of each error source was performed, and the results were finally verified through experiments. This analysis can guide the formulation of measurement schemes with low random error, and also provide theoretical support for subsequent improvement of measurement accuracy.